超声滚压轴承套圈表面强化的研究综述

首先介绍了超声滚压的强化机理，通过位错的湮灭与产生将晶粒细化至纳米级，晶粒细化导致位错塞积、缠结，使晶间滑移阻力变大，增加材料变形抗力。进而综述了超声滚压工艺参数、表面完整性(表面形貌、残余应力及显微结构)对轴承套圈耐磨损性能与抗疲劳性能的影响规律。最后，针对单一超声强化的不足，指出了超声滚压复合强化技术的发展方向。声电耦合可增加表层材料塑性流动，愈合微裂纹;超声滚压细晶作用可增加晶界数量，为离子提供了扩散通道，增加了离子注入浓度与深度;超声振动引起的空化效应和力学效应使熔覆层元素更均匀，降低熔覆层孔隙率，复合强化对超声滚压强化效果有明显的提升作用，可进一步增强轴承套圈强化效果。

Surface Strengthening of Ultrasonic Rolling Bearing Rings

Firstly, the paper introduces the strengthening mechanism of ultrasonic rolling:the grains are refined to nanometer level through the annihilation and generation of dislocations, and the grain refinement leads to dislocation stacking and entanglement, which increase the intergranular sliding resistance and the deformation resistance of materials; Furthermore, the paper summarizes the effects of ultrasonic rolling process parameters and surface integrity (surface morphology, residual stress and microstructure) on the wear resistance and fatigue resistance of bearing rings. Finally, in view of the shortcomings of single ultrasonic strengthening, the paper points out the development direction of the composite strengthening technology of ultrasonic rolling. Acoustic electric coupling can increase the plastic flow of surface material and heal micro cracks; The number of grain boundaries is increased by ultrasonic rolling, which provides diffusion channels for ions and increases the concentration and depth of ion implantation; The cavitation effect and mechanical effect caused by ultrasonic vibration make the elements of cladding layer more uniform and reduce the porosity of cladding layer. The composite strengthening can significantly improve the ultrasonic rolling strengthening effect, thereby further enhancing the strengthening effect of bearing rings.